C++ Will copy elision happen when returning a temporary object

Question

If I understand correctly copy elision will happen if an object is returned like this:

CSomeObject getObject(){

    //....
    //....
    return CSomeObject(...);
}

Is it safe to assume that copy elision will also happen here:

CSomeObject getObject(){

    CSomeObject some_object;
    some_object.setStuff();
    some_object.setMoreStuff();
    //....
    //....
    return some_object;
}

CSomeObject some_object = getObject();

There is only one return statement and always the same temporary object is returned. What about when the return is delegated / indirect:

CSomeObject getObject_2(){
    //....
    return getObject();
}

CSomeObject some_object = getObject_2();

score 1 · Accepted Answer · answered Jun 04 '17 at 11:35

1

"C++ Will copy elision happen when returning a temporary object" - it may. It's not guaranteed until C++17 (and even there, certain conditions apply). But, most compilers will elide the copy.

answered Jun 04 '17 at 11:35

Jesper Juhl

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C++ Will copy elision happen when returning a temporary object

1 Answers1